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71.
BACKGROUND: The aim of the present study was to highlight the advantages of treatment of bile duct injury (BDI) occurring during cholecystectomy on the basis of a multidisciplinary cooperation of expert surgeons, radiologists, and endoscopists. METHODS: Sixty-six patients had major BDIs or short- or long-term failures of repair. BDI was diagnosed intraoperatively in 27 patients (40.9%) and postoperatively in 39 (59.1%) patients. Among referred patients, 30 had complications from bile leak, 15 from obstructive jaundice, and 20 from recurrent cholangitis. Two patients died from sepsis after delayed referral before repair was attempted. Eleven additional patients had minor BDIs with bile leak both with and without choleperitoneum. RESULTS: Of patients with major BDI, surgical repair was performed in 41 (64.1%). Postsurgical morbidity rate was 15.8%, and there was no mortality. The rate of excellent or good results after surgical repair was 78.0% (32 of 41 patients), and this increased to 87.8% (36 of 41 patients) by continuing treatment with stenting in postsurgical strictures. Biliary stenting alone was performed in 23 patients (35.9%), with excellent or good results in 17 (73.9%). More than 200 endoscopic and percutaneous procedures were performed for initial assessment, treatment of sepsis, nonsurgical repair, contribution to repair, and follow-up. Patients with minor BDIs underwent various combinations of surgical and endoscopic or percutaneous treatments, always with good results. CONCLUSIONS: A multidisciplinary approach was of paramount importance in many phases of treatment of BDI: initial assessment, treatment of secondary complications, resolution of sepsis, percutaneous stenting before surgical repair, dilatation of strictures after repair, final treatment in patients not repaired surgically, and follow-up.  相似文献   
72.
Twenty-five percent of patients undergoing surgery for acute complicated diverticulitis represent emergencies. This condition is currently treated by colonic resection with primary anastomosis with or without colostomy, or by a Hartmann operation. We report on our experience with 52 consecutive patients with generalized peritonitis (8 cases), peri- and paracolonic abscesses (19 cases), severe pelvic abscesses (12 cases) and multiple abscesses with visceral fistulas (13 cases). All patients had emergency surgery. In 50/52 patients (96.2%) we performed a colonic resection with primary anastomosis using a mechanical stapler and in 2/52 a Hartmann operation. The overall mortality rate was 5.8%. The morbidity rate was 22% with 9 anastomotic leakages. A diverting colostomy was constructed in 16 patients and opened in only 8 patients. In 4 cases a parastomal hernia occurred after late closure and reduction of the colostomy. This data suggest that colonic resection with primary anastomosis, even without colostomy, is a safe procedure for the emergency treatment of acute complicated diverticulitis.  相似文献   
73.
74.
OBJECTIVE: We reviewed our experience in the surgical management of 80 patients with colorectal pulmonary metastases and investigated factors affecting survival. MATERIAL AND METHODS: From January 1980 to December 2000, 80 patients, 43 women and 37 men with median age 63 years (range 38-79 years) underwent 98 open surgical procedure (96 muscle-sparing thoracotomy, one clamshell and one median sternotomy) for pulmonary metastases from colorectal cancer (three pneumonectomy, 17 lobectomy, seven lobectomy plus wedge resection, six segmentectomy, three segmentectomy plus wedge resection and 62 wedge resection). Pulmonary metastases were identified at a median interval of 37.5 months (range 0-167) from primary colorectal resection. Second and third resections for recurrent metastases were done in seven and in four patients, respectively. RESULTS: Operative mortality rate was 2%. Overall, 5-year survival was 41.1%. Five-year survival was 43.6% for patients submitted to single metastasectomy and 34% for those submitted to multiple ones. Five-year survival was 55% for patients with disease-free interval (DFI) of 36 months or more, 38% for those with DFI of 0-11 months and 22.6% for those with DFI of 12-35 months (P=0.04). Five-year survival was 58.2% for patients with normal preoperative carcino-embryonic antigen (CEA) levels and 0% for those with pathologic ones (P=0.0001). Patients submitted to second-stage operation for recurrent local disease had 5-year survival rate of 50 vs. 41.1% of those submitted to single resection (P=0.326). CONCLUSIONS: Pulmonary resection for metastases from colorectal cancer may help survival in selected patients. Single metastasis, DFI>36 months, normal preoperative CEA levels are important prognostic factors. When feasible, re-operation is a safe procedure with satisfactory long-term results.  相似文献   
75.
Guo D  Fu T  Nelson JA  Superina RA  Soriano HE 《Transplantation》2002,73(11):1818-1824
BACKGROUND: Efficiency of engraftment after liver cell transplantation is less than 1% under conventional conditions. Our aim was to develop a high-efficiency, nonsurgical, no-genetic-advantage mouse model of liver repopulation with transplanted cells. METHODS: Mice were conditioned with nonlethal doses of a cell cycle inhibitor, retrorsine, 70 mg/kg, to irreversibly block proliferation of native hepatocytes. After the drug was eliminated, 2 million freshly isolated beta-galactosidase-labeled liver cells were transplanted into the spleens of C57BL/6J recipient mice. To stimulate donor cell proliferation, three doses of carbon tetrachloride (CCl4), 0.5 ml/kg, were given. Several control groups were studied to evaluate the contribution of each treatment to liver repopulation. RESULTS: Repopulation, as measured by cell isolation from recipient livers 1-7 months after transplantation, was on average 20%. Repopulation was 10% if CCl4 was given only once, between 0.5% and 1% if only retrorsine or CCl4 were used, and 0.05% if no conditioning was used. Phenotypically, whole livers turned blue on exposure to X-gal staining, whereas negative (control) livers remained pale brown. More than 55% of liver repopulation resulted from clusters containing 21 or more cells, some of which contained more than 200 cells, suggesting seven or more rounds of cell division in a subset of transplanted cells. CONCLUSION: This murine study demonstrates high levels of repopulation after liver cell transplantation into nongenetically modified livers, using a cell cycle inhibitor and chemical liver injury to provide transplanted cells a proliferative advantage. Liver repopulation was effected mostly by a small fraction of transplanted cells. Analogous nonsurgical liver cell transplantation strategies, but with clinically applicable drugs, could be devised for the treatment of liver-based metabolic diseases.  相似文献   
76.
The initial management of nonfunctioning pituitary macroadenomas (NFAs) is usually surgery; however, a significant proportion of NFAs may require further treatment. Radiotherapy is currently used in patients with residual tumour and achieves excellent long-term control, but there are concerns about potential late toxicity. Stereotactic radiotherapy, both in the form of radiosurgery or fractionated stereotactic radiotherapy, has been developed as a more accurate technique of irradiation with more precise tumour localization and consequently a reduction in the volume of normal tissue, particularly the brain, irradiated to high radiation doses. A review of the literature suggests that new radiation techniques offer safe and effective treatment for recurrent or residual pituitary adenomas; however longer follow-up is necessary to confirm the excellent tumour control and the potential reduction of long-term radiation toxicity. Currently, radiotherapy has an important role in patients with residual or progressive disease after surgery. Patients with small or no residual tumours after surgery may generally continue on a policy of surveillance without immediate irradiation, in order to avoid the potential toxicity of treatment.  相似文献   
77.
To analyze the outcomes between identical and compatible liver transplantation (OLT) for fulminant hepatic failure (FHF) from September 1984 to November 2005. The patients were divided in three groups; group 1 (identical), group 2 (compatible) and group 3 (incompatible), according to the donor-recipient blood type matching. We analyzed several outcomes regarding mortality, patient and graft survival, incidence of acute graft rejection during the first postoperative month (30 days), incidence of biliary complications and indications of re-transplantation. We also analyzed the relationship of Coomb's positive test with postoperative hemolysis to all the above mentioned factors. During the study period, 168 males and 112 females underwent their first OLT for FHF, with 37.1% overall mortality and 42.1% overall graft failure rate. The results between group 1 (203 patients) and group 2 (73 patients) were comparable. A statistically significant difference was recorded in 1 year and overall graft survival between group 1 and group 2 (P = 0.049 and log-rank = 0.035 respectively). Coomb's positive test did not influence the outcomes. OLT in FHF can be safely carried out whether the donor organs are identical or compatible. Hemolysis (Coomb's positive test) after identical or compatible OLT does not influence the outcomes.  相似文献   
78.

Background

Although nonoperative management is an accepted practice for most adults with focal nodular hyperplasia (FNH), questions remain about the safety and feasibility of this strategy in children. Our aim was to review the clinical features of children with FNH and determine current management patterns.

Methods

We reviewed records of all children and adolescents with FNH managed at our institution from 1999 to 2009 and performed a MEDLINE search to identify all published cases of FNH in the pediatric population.

Results

A total of 172 patients with FNH were identified, including 11 at our institution. The median age at diagnosis was 8.7 years and 66% were female. Median tumor size was 6 cm, and 25% had multiple lesions. Thirty-six percent were symptomatic at presentation. Twenty-four percent had a history of malignancy. Management included resection (61%), biopsy followed by observation (21%), and observation alone (18%). Indications for resection included symptoms (48%), inability to rule out malignancy (24%), tumor growth (15%), and biopsy-proven concurrent malignancy (9%).

Conclusions

Although FNH is a benign lesion that is typically managed nonoperatively in adults, most children with FNH currently undergo resection because of symptoms, increasing size, or inability to confidently rule out malignancy.  相似文献   
79.
Significant variation in the course of autosomal dominant polycystic kidney disease ( ADPKD) within families suggests the presence of effect modifiers. Recent studies of the variation within families harboring PKD1 mutations indicate that genetic background may account for 32 to 42% of the variance in estimated GFR (eGFR) before ESRD and 43 to 78% of the variance in age at ESRD onset, but the genetic modifiers are unknown. Here, we conducted a high-throughput single-nucleotide polymorphism (SNP) genotyping association study of 173 biological candidate genes in 794 white patients from 227 families with PKD1. We analyzed two primary outcomes: (1) eGFR and (2) time to ESRD (renal survival). For both outcomes, we used multidimensional scaling to correct for population structure and generalized estimating equations to account for the relatedness among individuals within the same family. We found suggestive associations between each of 12 SNPs and at least one of the renal outcomes. We genotyped these SNPs in a second set of 472 white patients from 229 families with PKD1 and performed a joint analysis on both cohorts. Three SNPs continued to show suggestive/significant association with eGFR at the Dickkopf 3 (DKK3) gene locus; no SNPs significantly associated with renal survival. DKK3 antagonizes Wnt/β-catenin signaling, which may modulate renal cyst growth. Pending replication, our study suggests that genetic variation of DKK3 may modify severity of ADPKD resulting from PKD1 mutations.Autosomal dominant polycystic kidney disease ( ADPKD) is the most common monogenic kidney disease worldwide, affecting one in 500 to 1000 births.1,2 It is characterized by focal development of renal cysts in an age-dependent manner. Typically, only a few renal cysts are clinically detectable during the first three decades of life; however, by the fifth decade, tens of thousands of renal cysts of different sizes can be found in most patients.3 Progressive cyst expansion with age leads to massive enlargement and distortion of the normal architecture of both kidneys and, ultimately, ESRD in most patients. ADPKD is also associated with an increased risk for cardiac valvular defects, colonic diverticulosis, hernias, and intracranial arterial aneurysms. Overall, ADPKD accounts for approximately 5% of ESRD in North America.2Mutations of PKD1 and PKD2 respectively account for approximately 85% and approximately 15% of linkage-characterized European families. Polycystin-1 (PC-1) and PC-2, the proteins encoded by PKD1 and PKD2, respectively, function as a macromolecular complex and regulate multiple signaling pathways to maintain the normal tubular structure and function.1 Monoclonal expansion of individual epithelial cells that have undergone a somatic “second hit” mutation, resulting in biallelic inactivation of either PKD1 or PKD2, seems to provide a major mechanism for focal cyst initiation,4 possibly through the loss of polycystin-mediated mechanosensory function in the primary cilium.5 In addition, a large prospective, observational study indicated that renal cysts in ADPKD expand exponentially with increasing age, and patients with large polycystic kidneys are at higher risk for developing kidney failure6; however, the key factors that modulate renal disease progression in ADPKD remain incompletely understood.Renal disease severity in ADPKD is highly variable, with the age of onset of ESRD ranging from childhood to old age.711 A strong genetic locus effect has been noted in ADPKD. Adjusted for age and gender, patients with PKD1 have larger kidneys and earlier onset at ESRD than patients with PKD2 (mean age at ESRD 53.4 versus 72.7 years, respectively).8,9 By contrast, a weak allelic effect (based on the 5′ versus 3′ location of the germline mutations) on renal disease severity may be present for PKD110 but not PKD2.11 Marked intrafamilial variability in renal disease is well documented in ADPKD and suggests a strong modifier effect.1015 In an extreme example, large polycystic kidneys were present in utero in one of a pair of dizygotic twins affected with the same germline PKD1 mutation, whereas the kidneys of the co-twin remained normal at 5 years of age.12 Several studies have quantified the role of genetic background in the phenotypic expression of ADPKD. In a comparison of monozygotic twins and siblings, greater variance in the age of onset of ESRD in the siblings supported a role for genetic modifiers.13 Two other studies of intrafamilial disease variability in PKD1 have estimated that genetic factors may account for 32 to 42% of the variance of creatinine clearance before ESRD and 43 to 78% of the variance in age at ESRD.14,15 The magnitude of the modifier gene effect from these studies suggests that mapping such factors is feasible. Here, we report the results of an association study of modifier genes for PKD1 renal disease severity.  相似文献   
80.
COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors’ liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.

  相似文献   

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